Field of the Invention
The invention relates to a method for computing an angle of rotation of a rotational-angle sensor apparatus with a first Hall measuring plate and a second Hall measuring plate which are arranged substantially orthogonally to each other.
Brief Description of the Related Art
The measurement of the angle of rotation of a rotating element is important in many cases, for example in the electronic commutation of synchronous motors, in an automatic transmission or when the position of a steering wheel, a position of a gearshift lever or a position for the accelerator pedal or the clutch is measured, and for ascertaining the height of the chassis (for adjusting the headlights).
The control of the electronic commutation is effected, for example, by means of control signals with which semiconductor switches are switched for controlling the coil array in the synchronous motor. For this purpose, the changes in the control signals for the commutation are derived from the angle φ of rotation of the rotor, wherein for measuring the mechanical angle of rotation (also called position angle) a rotational-angle sensor apparatus is used. The used rotational-angle sensor apparatus comprises two Hall measuring plates which are ideally arranged orthogonally to each other. Such a rotational-angle sensor apparatus 10 is shown, for example, in FIG. 2 with a first Hall measuring plate 20 and a second Hall measuring plate 30. Such rotational-angle sensor apparatus are known, for example from the published German application no. DE 10 2010 031 813.